The smell may enhance the ability to remember events and to remember to complete tasks at particular times, they said.

A group of 66 people were given memory tests in either a rosemary-scented room or another room with no scent.

Participants were tasked various tests to assess their memory functions, including finding hidden objects and passing specified objects to researchers at a particular time.

The results, presented at the British Psychological Society's annual conference in Harrogate, showed that participants in the rosemary-scented room performed better on the prospective memory tasks than those in the room with no smell.

"In this study we focused on prospective memory, which involves the ability to remember events that will occur in the future and to remember to complete tasks at particular times. This is critical for everyday functioning. For example, when someone needs to remember to post a birthday card or to take medication at a particular time."

"It supports our previous research indicating that the aroma of rosemary essential oil can enhance cognitive functioning in healthy adults, here extending to the ability to remember events and to complete tasks in the future.

"Remembering when and where to go and for what reasons underpins everything we do, and we all suffer minor failings that can be frustrating and sometimes dangerous. Further research is needed to investigate if this treatment is useful for older adults who have experienced memory decline."